Various types of electronic devices comprise power-detection circuitry, which verifies whether a power-supply voltage level is valid or not. Various power-detection schemes and circuit configurations are known in the art. For example, U.S. Pat. No. 5,886,549, whose disclosure is incorporated herein by reference, describes a device for neutralizing an electronic circuit when the electronic circuit is being powered or disconnected. The neutralizing device comprises a control circuit and a means to inhibit the operation of the electronic circuit, the control circuit activating the inhibiting means so long as a supply voltage remains below a threshold voltage or when the supply voltage goes below said threshold voltage.
U.S. Pat. No. 6,252,442, whose disclosure is incorporated herein by reference, describes a neutralization device for controlling an inhibiting circuit that blocks the operation of an electronic circuit when a supply voltage for the electronic circuit is not sufficient to ensure efficient operation of the electronic circuit.
U.S. Pat. No. 6,281,723, whose disclosure is incorporated herein by reference, describes a checking device for controlling the power-on or power-off operations in an integrated circuit. The device comprises a voltage reference circuit biased by a bias circuit, and an output stage. The device further comprises a control circuit to activate or deactivate the bias circuit as a function of the prevailing mode of operation of the integrated circuit, and a capacitor. A dynamic detection circuit is also associated with a transistor for discharging the capacitor.